The present invention generally relates to nanotechnology, and in particular, to differential amplifiers, current sources, and associated circuits created from carbon nanotubes, graphene nanoribbons and other related materials, and the associated use and synergies of these with carbon nanotube sensors, carbon nanotube actuators, and other nanoelectronic devices.
For carbon nanotube sensors and transducers, conventional consideration to interfacing to the larger-scale world of exogenous signal processing and control systems that would co-operate with these miraculous small devices is virtually or completely non-existent. One advantage of nanoscale molecular electronics (including carbon nanotube and graphene electronics) is that the degradation of signals and measurements due to thermal and other electrical noise can be highly reduced due in part to the smaller electron counts involved in nanoscale electronic device operation. However, with poor electrical interfacing to the larger-scale world, the valuable gifts and opportunities offered by the sensitivities and signal integrity of these nanoscale devices is easily (and perhaps literally) would otherwise be lost in the noise. The above comments can be extended to nanocomponents fabricated from other elongated semiconductor structures.
As a second observation, recognized benefits relate to signal conditioning, signal processing, and control electronics that are compatible with and complementary to the signal integrity of carbon nanotube sensors and transducers. In some circumstances such signal conditioning, signal processing, and control electronics would be purposed to work only with or within nanoscale devices (for example, a closed loop control system). In other circumstances such signal conditioning, signal processing, and control electronics would provide high-integrity interfacing between nanoscale devices and the larger-scale world of exogenous systems. The above comments can be extended to nanocomponents fabricated from other elongated semiconductor structures.
U.S. Pat. No. 7,858,918, entitled “Molecular Transistor Circuits Compatible with Carbon Nanotube Sensors and Transducers,” among other things describes small-signal and other circuit design techniques that can be realized by carbon nanotube field-effect transistors (CNFETs) and other types of carbon-based transistors to create analog electronics for analog signal handling, analog signal processing, and conversions between analog signals and digital signals.
As CNFETs exist and operate at nanoscale, they can be readily collocated or integrated into carbon nanotube sensing and transducing systems. Such collocation and integration can be at, or adequately near, nanoscale. In exemplary arrangements, a number of CNFETS and other carbon nanotube components can be used in analog operating modes and can be consecutively interconnected to form a chain on the same semiconducting carbon nanotube. A semiconducting carbon nanotube can be draped over an array of interconnecting and/or interfacing electrodes and insulating layers (for example as used to form the gate element of a CNFET). Natively N-type semiconducting carbon nanotube material can be locally converted to P-type by extracting oxygen through spatially localized photolithographed regions and sealing the region with an oxygen-barrier sealing layer. In various embodiments, carbon nanotube sensors, actuators, and transducers can be directly incorporated into analog circuits realized on the same nanotube. The above comments can be extended to nanocomponents fabricated from other elongated semiconductor structures.
U.S. Pat. No. 7,838,809, entitled “Nanoelectronic Differential Amplifiers and Related Circuits Having Carbon Nanotubes, Graphene Nanoribbons, or Other Related Materials,” among other things extends the electronics considerations further and with particular attention to the implementation of entire differential amplifiers on a single carbon nanotube, graphene nanoribbons, or other related materials. Optical interconnection systems and methods among circuit blocks, including the leverage of various types of isolation and multiplexing, are also taught. This patent and associated pending continuation applications also introduce the notions of “nanotube IP-cores” and “System-on-a-Nanotube” frameworks.
Pending U.S. Patent Application 61/217,535, entitled “Chain/Leapfrog Circuit Topologies and Tools for Printed Electronics, Carbon Nanotube/Grapheme Ribbon Nanoelectronics, and Their Confluences,” among other things explicitly extends the above and related approaches to printed electronics and semiconducting polymers. It also includes approaches for using printed electronics, either directly or via interpretation or supplement with numerical models, to used printed electronics to prototype circuits (using at least the design approaches presented) realized with carbon nanotubes, graphene nanoribbons, semiconducting polymers, and other related materials at various physical implementation scales.